Sheet feeding mechanism



1967 E. M. SPRINGER SHEET FEEDING MECHANISM 2 Sheets-Sheet 1 Filed Dec. 27, 1965 v INVENTOR EDWARD M. SPRINGER BY Oct. 24, 1967 E. M. SPRINGER 3,348,838

SHEET FEEDING MECHANISM Filed Dec. 27, 1965 2 Sheets-Sheet 2 Q E If? I v J Q A i m 5m SPQINGEQ INVENTO O %m E i. i f wwwfi 8 mm 1.. A I V L M Q Q NN @m h v Jhl N kn |H I n 1 i1 j m 61 6 Nm 0 ilth!! v m m E 3 2 N S 8 mm m United States Patent 3,348,838 SHEET FEEDING MECHANISM Edward M. Springer, Chicago, Ill., assignor to Heyer Inc., Chicago, Ill., a corporation of Illinois Filed Dec. 27, 1965, Ser. No. 516,489 11 Claims. (Cl. 271--24) ABSTRACT OF THE DISCLOSURE Side rails upstanding from feed table and laterally adjustable individually to guidingly engage one or both edges of a stack of sheets, each rail having a sheet corner engaging and single sheet releasing lip formed integrally therewith and pivoted rearwardly of lip to enable vertical movement of latter, means for guiding movements of the side rails and providing a unitary construction resistant to twisting forces and having center abutment stop means, and a counterbalance for the pivotal movements of the unit adjustable to vary the stack engaging pressure exerted by the lips to facilitate feeding of sheets of widely different physical characteristics of weight and flexibility.

This invention relates in general to means for receiving a stack of paper sheets or other sheet material and successively removing only the uppermost sheet from the stack and feeding each uppermost sheet so removed from the stack to apparatus for printing, folding, or otherwise utilizing such sheets.

Generally similar sheet feeding mechanisms designed specifically for use with duplicating and folding machines are disclosed in my US. Letters Patent No. 3,029,074, issued Apr. 10, 1962 and co-pending application Ser. No. 352,035, filed Mar. 16, 1964, issued March 8, 1966 as No. 3,239,212. These prior devices include a feed table for receiving and supporting a stack of paper sheets; side rails upstandingly mounted on the table to guidingly engage the edges of the sheets and maintain them in stack, which are laterally adjustable to accommodate sheets of different widths; abutment stop means for the inner or forward end of the stack; and a single sheet releasing finger overlying and engageable with each of the forward corners of the top sheet in the stack, the stop means and fingers being mounted on the table and slidably connected to the side rails for up-and-down movement relative thereto. According to the above-identified patent and application, feed rollers or other sheet advancing means are adapted to rest upon the uppermost sheet and urge it forwardly against corner abutment stop means whereby the forward corners of the sheet are buckled and released from the corner engaging fingers which are specifically shaped to facilitate such release, and the sheet is moved forwardly over the abutment stop means.

During successive sheet feeding operations, it is necessary that the corner engaging fingers be free to move downwardly and it is desirable that each maintains the same downward pressure on the uppermost sheet regardless of the height of the stack or number of sheets in it. It is also an advantage to be able to vary the degree of such finger pressure so as to render the mechanism operable with sheets of widely different physical characteristics of weight and flexibility or resiliency.

A principal object of this invention is the provision of sheet feeding mechanism having greatly improved operating characteristics because it avoids binding or resistance to vertical movements of sheet corner engaging fingers or lips and resulting impairment of their ingle sheet releasing function and insures proper relationship at all times between the center and corner abutment stop means and corner engaging lips or fingers.

This object is attained by providing a novel unitary 3,348,838 Patented Oct. 24, 1967 sheet restraining and releasing mechanism in which sheet corner engaging lips or fingers are formed integrally with or integrally attached to the side rails and the latter are pivotally mounted rearwardly of those lips to enable the necessary vertical movements of the latter. The stack restraining means thus provided also includes novel means for guiding vertical and lateral movements of the side rails and their sheet corner engaging lips relative to the feed table and to each other, together with an upwardly extending stack restraining member formed integrally therewith which comprises the center abutment stop means. The attainment of this object is further assured by a unitary construction of parts making a rigid assembly, pivotally mounted rearwardly of the sheet corner engaging lips, which is resistant to twisting forces, such as those resulting from application of a lifting force to only one of the side rails.

A further important object of the invention thus also is attained, which is to simplify and materially reduce the cost of production of sheet releasing mechanism of this character.

Another object is to facilitate feeding of sheets of widely different flexibility or resiliency, and this is attained by providing means for selectively varying the downward or stack engaging pressure exerted by the corner engaging lips.

Numerous other objects and advantages of the invention will be apparent as it is better understood from the following description, which, when taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

In the drawings:

FIGURE 1 is a plan View of a sheet guiding, restraining and releasing mechanism embodying the features of this invention;

FIG. 2 is a vertical sectional view taken substantially on the line 22 of FIG. 1 and showing a portion of a machine with which the sheet feeding mechanism may be associated;

FIG. 3 is a transverse sectional view taken substantially on the line 33 of FIG. 1; and

FIG. 4 is a detail elevational view, as seen in the direction of the line 4-4 of FIG. 1.

Referring more particularly to FIGS. 1 and 2, reference numeral 11 indicates in general a table for a sheet feeding mechanism embodying the features of this invention which is adapted to support a stack of sheets 12, shown in broken lines in FIGS. 1 and 3, on a machine, such as a duplicator or folding machine, a portion of which is shown in FIG. 2 and designated generally by reference numeral 13. The machine 13 includes side flanges 14 and sheet advancing means, which are illustrated herein in the form of rollers 15 mounted on a shaft 16 extending transversely of the table 11 and through slots 17 in the side flanges 14. Since the specific means for mounting and rotating the feed rollers 15 is not part of the instant invention, reference may be had to my prior United States Letters Patent No. 2,975,707, issued Mar. 21, 196 1, for the details of suitable such sheet advancing means, it being understood that the rollers 15 and their shaft 16 are mounted for up and down movements, as between the upper position of FIG. 2 wherein the rollers 15 rest upon the stack of sheets 12, and the lower position shown in FIG. 2 into which they fall by gravity upon removal of the bottom sheet in the stack. As is customary with such sheet feeding mechanisms, deflectors 18 are provided for guiding each sheet, as it is advanced from the stack by the rollers 15, into proper alignment and engagement with machine rollers 19. It will be understood, of course, that the sheet guiding, restraining and releasing means of this invention may be employed with any suitable form of sheet advancing means other than the rollers 15.

The table 11 preferably is formed of a unitary metal stamping provided with depending side flanges 21 and a plurality of laterally spaced, feed roller receiving apertures 22 adjacent its forward end. The feed rollers 15 are mounted on their shafts 16 for lateral adjustment to accommodate sheets of different widths and when the last sheet in a stack has been fed from the table 11, in the manner later to be described, the feed rollers 15 by gravity will fall into appropriate ones of the apertures 22 into the lowermost position illustrated in FIG. 2. As is well known, the purpose of such final downward movement ,of the feed rollers is to effect automatic stopping of the machine when the latter is motor driven and, in lieu of the apertures 22, the table may be formed with a suitable transversely extending depression to accommodate the rollers 15 in their lowest position of FIG. 2. The table 11 also is provided with a pair of laterally extending apertures 23 disposed rearwardly of the apertures 22 and a second pair of laterally extending apertures 24 near its rear end, both for purposes which will be readily apparent hereinafter. To avoid catching or interference with the lower sheets of a stack when the same is being placed on the table 11 into operative position, the forward edge of each of the apertures 23 may be formed as a downwardly sloping lip 25.

Mounted on the table 11 for guidingly engaging the lateral edges of the sheets in any stack of sheets 12 are a pair of side rails, indicated generally by reference numeral 26. Each of the rails 26 preferably may be provided with a manually engageable and outwardly extending flange 27 at its upper edge and a horizontalflange 28 extending inwardly from the rear end of its lower edge. Means are provided for laterally slidably supporting each side rail 26 which includes, in the illustrated embodiment, an inverted U-shaped bracket 29 having a central horizontal portion welded or otherwise secured to and depending from the end flange 28, and depending ears or end flanges 31 with non-circular apertures slidably engaging or receiving the main portion of a transversely extending rod 32 having a substantially identical noncircular cross-sectional shape (FIG. 2). The end portions of the transverse rod 32 are circular in cross section and journaled in any suitable manner, as in the depending side flanges 21 of the table 11, although the rod need not necessarily be disposed below the sheet supporting surface of the table. For counter-balancing purposes, the left-hand end of the rod 32 may be provided with a counterweight 33 rotatably mounted thereon in off-center relation to its mass and'adapted to be secured to the rod in any selected rotatably adjusted position by means of a set screw 34 (FIGS. 1 and .4).

With the above described arrangement, the side rails 26 are laterally slidably on thettransverse rod 32 and rotatable therewith relative to the table 11. If desired, means may be provided for positively securing each side rail 26 in any laterally adjusted position. In the illustrated embodiment, such means comprises an elongated set screw 35 extending through a suitable tapped aperture in thehorizontal portion of each U-shaped bracket 29 for clamping engagement with, and disengagement from, the upper surface of the non-circular portion of the rod 32. It will be appreciated that the previously noted laterally extending apertures 24 are disposed adjacent the rear end of table 11 to provide clearance for the rear portions of the side rails 26 and such set screws 35 during pivotal movement of the side rails and to enable the desired lateral adjustments of the latter relative to the table.

Intermediate its ends, each of the side rails 26 is provided with a depending portion 36 which extends downwardly through the associated laterally extending aperture 23. As best seen in FIGS. 2 and 3, each such depending portion 36 has a substantially rectangular aperture 37 which slidably engages or receives the laterally extending portion of a slide member 38. This member 38 may be provided as means for insuring rigidity and assisting in effecting unitary vertical movements of the two side rails 26. The transversely extending slide member 38 preferably comprises a sheet metal stamping in cruciform shape with depending edge flanges 39, provided primarily for strengthening purposes, and with a forwardarm 41 terminating in an upwardly extending stack restraining member 42 extending through a transverse slot 43 adjacent the forward end of table 11. This upwardly extending member 42 comprises a center abutment stop means to limit forward movement of the stack of sheets 12 on the table 11.

The remaining portion of the cruciform-shaped slide member 38 comprises a rearwardly extending arm 44 which is slidably engaged between the depending arms of an inverted U-shaped guide bracket 45 that is secured at its upper end in any suitablemanner, as by welding, to the bed portion of the table 11. The bracket 45 maintains the center abutment stop means 42 against lateral displacement and guides its vertical movements. Friction means may be interposed between each of the interconnecting or depending portions 36 of the side rails 26 and the slide'member 38 to resist lateral movements of the side rails and, if desired, to function to frictionally retain the same in laterally adjusted position in lieu of the positive locking set screws 35. In the illustrated embodiment, this friction means comprises a leaf spring 46 se-.

cured in any suitable manner adjacent its inner end at 47 to the transversely extending slide member 38,with its free outer end extending through the aperture 37 in the associated side rail 26 to urge the latter downwardly and maintain the same in frictional engagement with the slide member 38.

To assure rigidity of each side rail structure, means may be provided in the form of braces 48, each of which is secured at its forward end in any suitable manner to the lower part of one of the depending portions 36, with its rearward end being secured to the lower part of the inner car 31 of the associated bracket 29. And these members, particularly 26, 29, 32, and 48, comprise a rigid assembly mounted for pivotal movement as a unit which is resistant to twisting forces, such as those resulting from lifting of the assembly by means of only one of the outwardly extending flanges 27.

Formed integrally withor integrally attached in any suitable manner to each side rail 26 and preferably comprising an angularlyinwardly extending portion of the forward end of the horizontal flange 27, is a single sheet releasing lip 49 adapted to overlie and engage with the associated forward corner of the uppermost sheet in the stack of sheets 12 when the latter is disposed in contact with the center abutment stop member 42 and the associated side rail 26 is in contact with the adjacent edges of the sheets in the stack.

The forward end of each side rail 26 and its substantially horizontal flange 27,'including the lip 49, terminates in a substantially vertical depending portion 51, the lower end 52 of which may be forwardly and downwardly inclined. Each of these depending portions 51 of the side rails 26 comprise corner abutment stop means for 'cooperation with, and in the-same substantially vertical plane as that defined by. the rear face of, the center abutment stop means 42 to limit forward movement of the stack of sheets on the table. As is seen best in FIG; 2, the upper end of thecenter abutment stop means 42 prefer: ably terminates so as to be spaced at short distance below the lower surfaces of the lips 49. The slide member 38 and its interconnection with the side rails 26 functions to maintain thisvertical relationship between the upper end of stop 42 and the sheet corner engaging lips 49.

In operation or use, the sheet advancing means or feed rollers 15 first are raised to an uppermost position above the upper one illustrated in FIG. 2 where the same are latched in well-known manner.v As is also known in the.

art, so positioning the feed rollers may be employed to turn olf or prevent energization of the motor if the motor if the machine 13 is motor operated. A stack of sheets 12 of any desired number and any suitable size preferably then is placed on the table 11 with the forward edges of the sheets abutting against the center stop means 42. The side rails 26 then may be lifted as a unit and individually adjusted laterally, as required by the width of the sheets in stack and the desired lateral position of the stack, and released to permit gravity to lower the same about their common pivot, comprising the transverse rod 32, so that the lips 49 engage and press downwardly upon the forward corners of the uppermost sheet in the stack. In this connection, if positive means for locking the side rails 26 against lateral movement in such adjusted positions is not employed, such as the set screws 35, reliance may be placed solely upon frictional holding means, such as the leaf springs 46.

The degree of downward pressure thus exerted by the sheet corner engaging and releasing lips 49 may be selectively varied by suitable adjustable positioning of the counterbalance 33. This facilitates the feeding of sheets of differing physical characteristics, all the way between those of very appreciable stiffness and those, such as onion skin paper, of light weight and very little resistance to flexing.

As seen in FIGS. 1 and 2, the rearward surfaces of the center and corner abutment stops 42 and 51 limit forward movement of the stack of sheets. The center stop extends downwardly to a point below the stack supporting surface of table 11 to facilitate placement of the stack when one or both of the side rails 26 are spaced from the stack. The corner stops 51 need cooperate only with the sheets at the top of the stack, so it is not necessary that they extend downwardly very far from the lips 49. Of course, it will be understood that the center stop 42 may be omitted, but it then would be preferable to extend the corner stops 51 downwardly to below the top of table 11 when the side rails are in their upper position of FIG. 2.

It will be appreciated from FIG. 2 that upward pivotal movement of the side rails 26 in the embodiment specifically illustrated will not raise the feed rollers 15 from their lowermost position in which they rest in selected ones of the apertures 22 in the table 11, because the uppermost position of the top flanges 27 of the side rails, as shown in that figure, will not then contact the transverse feed roller shaft 16. Since the sole function of the flanges 27, aside from strengthening the side rails 26, is as manually engageable means for swinging the rails upward, and as such does not require much elfort, the whole of each flange 27 except its rearmost portion may be dispensed with, if desired. In such case, or even if the flanges 27 are employed as herein illustrated, the lips 49 and/or the corner abutment stops 51 may either be made integrally with their associated side rails or rigidly secured thereto in any suitable manner. In any event, after the stack of sheets to be fed serially into the machine 13 has been so positioned on the table 11 with either one or both of the lips 49 engaging and resting upon a forward corner of the stack, the feed rollers 15 or sheet advancing means may be lowered into contact with the uppermost sheet in the stack in well-known manner.

Thereafter, as such sheet advancing means urges the uppermost sheet of the stack forwardly (to the right in FIG. 2), the abutment stop means, herein comprising the center stop 42 and/or one or both of the corner abutments 51, will impede such forward feeding of that uppermost sheet. The sheet corner engaging lips 49 are so shaped and disposed to permit such attempted forward feeding to cause the uppermost sheet to buckle and thereby release its forward end from the abutment stop means and enable that single sheet to be fed forwardly against and between the deflectors 18 and into proper engagement with the machine rollers 19.

By virtue of the above-described pivot-a1 arrangement of the sheet guiding, restraining and releasing means, such feeding operations will be effected in similar manner regardless of the number of sheets in the stack (up to the machines capacity) and until the last sheet thus has been removed from the table 11. At that point, the feed rollers 15 will assume their lowermost position of FIG. 2 and, as previously noted, may thus automatically terminate the feeding operation by turning off the motor if the machine is motor driven. The unitary construction of each of the side rails 26 and its sheet releasing lip 49 and corner abutment stop means 51 combines wit-h such pivotal mounting of the side ralis to avoid any binding or resistance to the vertical movements of the sheet corner engaging lips and impairment of their single sheet releasing function. The operations of these rails and their lips 49 are further improved by virtue of the unitary character of their pivotally mounted assemblage, which may include the braces 48 interconnecting the intermediate and rear portions of the side rails 26 below the table 11.

It will also be appreciated from the foregoing description that, in addition to said improved operating char acteristics, this novel sheet guiding, restraining and releasing mechanism greatly reduces the cost of its production because of the simplicity of the parts, such as the integral construction of the sheet corner engaging lips with each associated side rail. This unitary construction and that of the slide member 38 lend themselves to manufacture by simple stamping operations, and it will be appreciated that the side rails 26 and their integral lips 49 and abutment stop means 51 may readily be constructed of plastic to further reduce the cost of manufacture, if desired.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

1. In sheet feeding mechanism having a table for supporting a stack of sheets and sheet advancing means for urging the uppermost sheet of a stack forwardly, sheet guiding, restraining and releasing means, comprising abutment stop means for engaging a forward edge of the sheets, a single sheet releasing lip overlying and engageable with a forward corner of the uppermost sheet in a stack, and a side'rail integrally related to said lip and extending downwardly to said table for guidingly engagingan edge of the sheets in a stack and pivotally supported by the table rearwardly of said lip to enable vertical movement of the latter without binding and the maintenance by said lip of a predetermined downward pressure on the uppermost sheet regardless of the height of the stack or number of sheets in it.

2. Sheet feeding mechanism according to claim 1, wherein said abutment stop means comprises a corner abutment formed integrally with said side rail and sheet corner engaging lip.

3. In the sheet feeding mechanism of claim 1, a second side rail having a single sheet releasing lip integrally related therewith for overlying and engaging a second forward corner of the uppermost sheet in a stack and pivotally supported by the table on the axis of the pivot for the first said side rail, said side rails being mounted for lateral adjustment relative to each other to accommodate sheets of different widths.

4. In the sheet feeding mechanism of claim 3, means for guiding vertical and lateral movements of said side rails, comprising a transversely extending member supported by said table and slidably engageable with each of said side rails.

5. In sheet feeding mechanism according to claim 4, a

transversely extending slide member engageable with said side rails and having a forwardly extending portion formed integrally therewith and terminating in an upwardly extending stack retaining member comprising said abutment stop means.

6. In sheet feeding mechanism according to claim 3,

a transversely extending rod rotatably supported by said table, and means slidably mounting each said side rail on said rod to facilitate their lateral adjustment to accommodate sheets of different widths and, with said rod, to effect the pivotal support of said side rails and sheet, corner engaging lips.

7. In the sheet feeding mechanism of claim 6, friction means for resisting lateral movements of said side rails and frictionally retaining the same in laterally adjusted position.

8. In the sheet feeding mechanism of claim 6, brace means interconnecting the means slidably mounting each said side rail on said rod and the associated side rail to a point spaced forwardly of said rod.

9. In the sheet feeding mechanism of claim 3, means for counterbalancing the pivotal movements of said side rails to assure said predetermined downward pressure by said sheet corner engaging lips and adjustable for selectively varying the downward pressure by said sheet corner engaging lips to facilitate feeding of sheets of differing physical characteristics.

10. In sheet feeding mechanism having a table for supporting a stack of sheets and sheet advancing means for urging the uppermost sheet of a stack forwardly,

sheet guiding, restraining and releasing means, comprising abutment stop means for engaging a forward edge of the sheets, a single sheet releasing lip overlying and engageable with a forward corner of the uppermost sheet in a stack, and a side rail integrally relatedto said lip and extending downwardly to said table for guidingly engaging an edge of the sheets in a stack and supported by the table rearwardly of said lip to enable vertical movement of the lip without binding and the maintenance by said lip of a predetermined downward pressure on the uppermost sheet regardless of the height of the stacker number of sheets in it.

11. In the sheet feeding mechanism of claim 10, a second side rail having a single sheet releasing lip integrally related wtherewith for overlying and engaging a second forward corner of the uppermost sheet in a stack and supported by the table rearwardly of said lip, said side 1 rails being mounted for lateral adjustment relative to each other to accommodate sheets of different widths.

References Cited UNITED STATES PATENTS 2,710,752 6/ 1955 Fergnani 271-6 1 X 2,893,729 7/ 1959 Perzentka 271-2l 3,278,180 10/1966 Sleeper 27119 3,285,601 11/ 1966 Zeuthen 271-22 M. HENSON WOOD, 111., Primary Examiner.

R. A. SCHACHER, Assistant Examiner. 

1. IN SHEET FEEDING MECHANISM HAVING A TABLE FOR SUPPORTING A STACK OF SHEETS ADVANCING MEANS FOR URGING THE UPPERMOST SHEET OF A STACK FORWARDLY, SHEET GUIDING, RESTRAINING AND RELEASING MEANS, COMPRISING ABUTMENT STOP MEANS FOR ENGAGING A FORWARD EDGE OF THE SHEET, A SINGLE SHEET RELEASING LIP OVERLYING AND ENGAGEABLE WITH A FORWARD CORNER OF THE UPPERMOST SHEET IN A STACK, AND A SIDE RAIL INTEGRALLY RELATED TO SAID LIP AND EXTENDING DOWNWARDLY TO SAID TABLE FOR GUIDINGLY ENGAGING AN EDGE OF THE SHEET IN A STACK AND PIVOTALLY SUPPORTED BY THE TABLE REARWARDLY OF SAID LIP TO ENABLE VERTI CAL MOVEMENT OF THE LATTER WITHOUT BINDING AND THE MAIN TENACE BY SAID LIP OF A PREDETERMINED DOWNWARD PRESSURE ON THE UPPERMOST SHEET REGARDLESS OF THE HEIGHT OF THE STACK OF NUMBER OF SHEET IN IT. 